This invention relates to a removable jet propulsion unit for a watercraft and more particularly to an improved watercraft construction having a removable jet propulsion unit.
The advantages of jet propelled watercraft are well known. If the watercraft is powered by a jet propulsion unit that is mounted within a tunnel positioned at the rear end of the hull of the watercraft, the overall configuration of the watercraft can be quite smooth and sleek. However, when the jet propulsion unit is mounted in such a tunnel, certain difficulties arise. Specifically, the jet propulsion unit tends to be submerged at all times, even when the watercraft is not being operated, and barnacles and other incrustation can form on the water inlet portion of the unit.
There have been proposed, therefore, arrangements wherein the jet propulsion unit is movable between a normal position within the tunnel and a raised position in which the water inlet opening is disposed out of the body of water in which the watercraft is operating. This avoids these disadvantages. In addition, arrangements have been provided wherein the water inlet opening may be rotated to an upwardly facing position so as to permit foreign material to be cleaned from the water inlet portion of the jet propulsion unit.
In watercraft embodying such movable jet propulsion units, it has been the practice to have the tunnel extend completely through the rear of the hull of the watercraft and thus, a relatively large opening is formed at the rear of the watercraft. This large opening is somewhat further enlarged so as to permit access to the jet propulsion unit even when it is in its raised out of the water position. As a result, the hull of the watercraft may be weakened to some extent.
The provision of the large rear opening for the tunnel has also been employed so as to facilitate removal and servicing of the jet propulsion unit from the tunnel. In this way, the jet propulsion unit can be removed from the hull even when the watercraft is in the body of water. However, the disadvantages of this type of construction have been already noted.
It is, therefore, a principal object of this invention to provide an improved hull construction for a jet propelled watercraft.
It is a further object of this invention to provide a jet propelled watercraft of the type wherein the jet propulsion unit may be movable within the tunnel and can be easily removed.
It is a further object of this invention to provide a removable arrangement for the jet propulsion unit of a watercraft and wherein the removal is facilitated through a small opening in the transom of the watercraft so as to permit a high strength hull design.